Tube-bending machine

ABSTRACT

The invention belongs in the field of machines for bending tubes and refers in particular to a machine ( 1 ) comprising a supporting base ( 2 ), a positioning device ( 3 ) for the tube ( 7 ) to be bent and a bending device ( 4 ) for said tube ( 7 ) characterised by having devices capable of rotating through up to 360° in order to bend said tube ( 7 ) in various bending planes, including starting alternatively from either end of said tube or, as necessary, at an intermediate part.

This application claims priority to Italian Patent Application No.MI2007A001355 filed on Jul. 9, 2007, which is hereby incorporated byreference.

OBJECT OF THE INVENTION

The present invention relates to a machine for bending tubes of anylength (short, medium or long) without having to withdraw the tube to bebent, in order to effect curves with a different radius and/or indifferent bending planes.

The machine which is the subject of the present invention is alsosuitable for bending tubes designated as hybrid, that is to say tubesformed from lengths of metal and lengths of rubber or other non-metallicmaterial.

THE STATE OF THE ART

Tube-bending machines are known which bend tubes by setting about thebending starting from one end of the tube to be bent and keeping theother end of said tube in the positioning device. Tubes bent with saidknown machines have the disadvantage of oscillating and/or undergoingdeformation subsequently to bending because they are left lackingadequate support, in a so-called overhanging position, that is to sayrestrained at a single point and subjected to the force of gravity.

In relation to the bending of tubes generally designated hybrid, that isto say tubes formed from lengths of metal and lengths of rubber or othernon-metallic material, the known tube-bending machines have greatdifficulty in bending said hybrid tubes, because said machines set aboutbending the tube starting from just one end of said tube, and thebending devices can easily touch the non-metallic parts of the tube,with the risk of damaging it.

Among tube-bending machines, an orbital machine for bending long tubesis also known, described in document U.S. Pat. No. 7,093,475. Saidmachine includes a bending head mounted on a U-shaped arm which rotatesaround the horizontal axis of the tube to be bent. The machine describedin said document has the disadvantage of being able to manipulate tubesof small size because the weight of the head mounted on theabove-mentioned U-shaped arm must be small for structural reasonsrelating to the shape of said arm. Furthermore, the length of the tubesto be bent is anyway limited by the breadth of the U which constitutesthe above-mentioned arm, the overall dimensions of the bent tube beinglimited by the breadth of the U formed by the above-mentioned arm.

The machine described in document U.S. Pat. No. 7,093,475 is capable ofbending tubes only in one plane of curvature, having therefore a limitedproductive capacity.

DESCRIPTION OF THE INVENTION

An object of the present invention is to create a machine for bendingmetal or hybrid tubes, that is to say tubes formed from lengths of metaland lengths of rubber or other non-metallic material, of any size andlength, with characteristics which are such as to be able to overcomethe disadvantages mentioned with reference to the known art.

These and other objects are achieved by means of a tube-bending machinecharacterised by comprising a positioning arm equipped with means forrotating through up to 360° around the central axis of the tube to bebent and one or more locking devices suitable for rotating through up to360° around one or more fulcrums.

This and other characteristics will become clearer from the followingdescription of some embodiments illustrated, purely by way ofnon-limiting example in the attached drawings in which:

FIG. 1 shows a perspective view of the whole of a tube-bending machinewhich is the subject of the present invention with a positioning devicesuitable for rotating through up to 360°;

FIG. 2 shows the machine of FIG. 1 highlighting the locking device andthe means suitable for rotating said device up to 360° around fulcrum(F);

FIG. 3 shows the machine of FIG. 1 highlighting the two locking devicesand the means suitable for rotating said devices up to 360° aroundfulcrums (F) and (G);

FIG. 4 shows the machine of FIG. 1 with a second bending device.

With reference to FIG. 1, no. (1) indicates a machine for bending tubes,consisting of a supporting base (2) which supports a positioning device(3) for the tube to be bent (7) of wholly metallic or hybrid type, thatis to say formed from lengths of metal and lengths of rubber or othernon-metallic material, by one or more devices (4) for bending the tube(7) to be bent. Said positioning device (3) consists of a turret (5) anda positioning arm (6).

Said machine also includes means known to persons skilled in the art forthe purpose of making the positioning device (3), by means of thetranslation of turret (5) and/or device (4), take up mutual positionsfor the purpose of allowing said device (4) to be moved, according tomethods known to persons skilled in the art, for the purpose of bendingsaid tube (7) on the basis of the preset work programme.

Said FIG. 1 also shows the positioning device (3) provided with means(8) for rotating the positioning arm (6) through up to 360° around thecentral axis (Y) of the tube (7) to be bent, so as to be ableadvantageously to bend said tube (7), particularly of hybrid type, invarious bending planes having in common said central axis (Y), havingamong other things the possibility of locking the tube in theintermediate area and being able to start indifferently from either ofits ends, thus overcoming the disadvantages of the known machines.

FIG. 2 shows the machine of FIG. 1, highlighting the positioning arm (6)equipped with a locking device (9) for the tube (7) to be bent. Saidlocking device (9) is provided with means (10) for rotating through upto 360° around a fulcrum (F) so as to rotate said tube (7) for thepurpose of being able to bend either end of said tube (7) alternativelyby means of device (4) on the basis of a preset work programme.

FIG. 3 shows the machine of FIG. 1, demonstrating another embodimentaccording to which the positioning arm (6), equipped with two lockingdevices (12) and (13) for the tube (7) to be bent, is provided withmeans (10) and (11) for rotating through up to 360° around fulcrum (F)and fulcrum (G) so as to rotate said tube (7) for the purpose of beingable to bend either end of said tube (7) alternatively and/or anintermediate part of said tube by means of device (4) on the basis of apreset work programme.

FIG. 4 shows the machine of FIG. 1, equipped with a further bendingdevice (14) capable of moving and being moved by known movement means.Equipping machine 1 with further possibilities of bending enables aconsiderable increase in the possibilities of bending said tube (7).

Machine 1 can be susceptible of numerous variations particularly asregards the positioning of the elements without thereby departing fromthe protective compass of the claims set out below.

1. A tube-bending machine, comprising: a supporting base, a positioningdevice for the tube to be bent, at least one device for bending the tubeto be bent, means for making the positioning device and the bendingdevice for bending said tube take up mutual positions for bending saidtube, wherein said positioning device includes a turret and apositioning arm equipped with means suitable for rotating saidpositioning arm through 360° around the central axis (Y) of the tube tobe bent, in order to position said tube for the purpose of being bent bymeans of said bending device in various bending planes.
 2. Atube-bending machine according to claim 1 wherein said positioning armis equipped with at least one locking device for the tube to be bentequipped with means suitable for rotating said locking device through upto 360° around a fulcrum (F) in order to rotate said tube for thepurpose of bending either end of the tube alternatively by means of saidbending device.
 3. A tube-bending machine according to claim 1 whereinsaid positioning arm is equipped with two locking devices for the tubeto be bent and means suitable for rotating said devices through up to360° respectively around a fulcrum (F) and a fulcrum (G) in order torotate said tube for the purpose of bending either end of tubealternatively by means of said bending device.
 4. A tube-bending machineaccording to claim 1 that further comprises at least one second bendingdevice.
 5. A tube-bending machine according to claim 2 that furthercomprises at least one second bending device.
 6. A tube-bending machineaccording to claim 3 that further comprises at least one second bendingdevice.